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Radionuclide Dosimetric Data Sheets

Einsteinium-254

Summary data

General

Classification

Isotope:  Es-254
Atomic number (Z):  99
Mass number (A):  254
Neutron number (N):  155

Radioactive decay

Decay modes:  α, β-, Spontaneus fission
Half-life:  275.7 [d]
Decay constant:  2.9099e-08 [1/s]
Daughters:  Bk-250 (100.0%), Fm-254 (0.000174%), SF (3e-06%)
Radioactive daughters:  Bk-250, Fm-254

Dosimetric constants

Mean alpha energy:  6.5243 [MeV]
Mean electron energy:  0.07266 [MeV]
Mean photon energy:  0.0208 [MeV]
Air kerma rate constant, Γ10:  1.530e-17 [Gy·m2/Bq·s]
Air kerma coefficient, Kair:  1.530e-17 [Gy·m2/Bq·s]
Equilibrium dose constant for weakly-penetrating radiations (α and/or electrons), Δwp:  1.057e-12 [Gy·kg/Bq·s]
Equilibrium dose constant for alphas, Δα:  1.045e-12 [Gy·kg/Bq·s]
Equilibrium dose constant for betas/electrons, Δβ-,β+,e-:  1.164e-14 [Gy·kg/Bq·s]
Equilibrium dose constant for photons, Δp:  3.333e-15 [Gy·kg/Bq·s]

Summary spectra (plot)

Spectra source:  ICRP Publication 107: Nuclear Decay Data for Dosimetric Calculations. Ann. ICRP 2008, 38 (3).

Download tabulated summary spectra file here:  www.mirdsoft.org/products/MIRDspecs/Es-254 Summary Spectrum.csv

Beta spectra (plot)

Spectra source:  ICRP Publication 107: Nuclear Decay Data for Dosimetric Calculations. Ann. ICRP 2008, 38 (3).

Download tabulated beta spectra file here:  www.mirdsoft.org/products/MIRDspecs/Es-254 Beta Spectrum.csv

 

Tabulated data

Summary spectra (table)

Spectra source:  ICRP Publication 107: Nuclear Decay Data for Dosimetric Calculations. Ann. ICRP 2008, 38 (3).

Note: Radiations with yield < 0.01 are excluded from the table, but are available in the linked *.csv data.

Download tabulated summary spectra file here:  www.mirdsoft.org/products/MIRDspecs/Es-254 Summary Spectrum.csv

 

Energy [MeV]

Yield [#/nt] if > 0.01

Radiation type

7.83079e-05

3.284e+01

X-ray

3.76436e-03

2.178e-01

X-ray

5.83200e-03

1.746e-02

X-ray

1.29387e-02

2.416e-02

X-ray

1.50951e-02

3.662e-02

X-ray

1.53277e-02

3.214e-01

X-ray

1.85632e-02

6.977e-02

X-ray

1.91452e-02

8.442e-02

X-ray

1.93317e-02

1.427e-02

X-ray

2.01361e-02

6.576e-02

X-ray

2.03253e-02

6.328e-02

X-ray

2.35469e-02

1.558e-02

X-ray

2.37400e-02

2.322e-02

X-ray

2.40574e-02

2.058e-02

X-ray

6.30000e-02

2.000e-02

Gamma

1.03860e-04

9.113e+00

Auger electron

1.91270e-04

5.155e+00

Auger electron

1.99964e-04

4.657e-02

Auger electron

3.06065e-04

8.711e+00

Auger electron

6.49385e-04

1.845e+00

Auger electron

1.12000e-03

2.998e-01

Conversion electron

2.27893e-03

8.342e-01

Auger electron

2.74224e-03

2.543e+00

Auger electron

3.03140e-03

7.000e-01

Conversion electron

3.38350e-03

5.934e-01

Auger electron

4.13034e-03

3.812e-02

Auger electron

8.00000e-03

2.550e-01

Conversion electron

9.10600e-03

2.001e-01

Conversion electron

9.89700e-03

2.211e-02

Conversion electron

1.02060e-02

3.171e-01

Conversion electron

1.09970e-02

1.511e-02

Conversion electron

1.14999e-02

4.389e-01

Auger electron

1.54027e-02

2.339e-01

Auger electron

1.60380e-02

1.620e-01

Conversion electron

1.73060e-02

6.635e-01

Conversion electron

1.80970e-02

7.363e-02

Conversion electron

1.93700e-02

2.925e-02

Auger electron

2.94314e-02

5.489e-02

Conversion electron

3.05314e-02

1.486e-01

Conversion electron

3.44000e-02

2.042e-02

Conversion electron

3.55000e-02

5.719e-02

Conversion electron

3.76314e-02

1.822e-01

Conversion electron

4.26000e-02

6.793e-02

Conversion electron

4.51060e-02

1.605e-02

Conversion electron

6.35791e+00

2.607e-02

Alpha

6.41550e+00

1.805e-02

Alpha

6.42681e+00

9.336e-01

Alpha

1.01793e-01

2.607e-02

Alpha recoil

1.02715e-01

1.805e-02

Alpha recoil

1.02896e-01

9.336e-01

Alpha recoil

 

Useful Links

Isotope decay characteristics are periodically updated as better measurements can be made - changes that may not be reflected on this page. Please see useful links:

National Nuclear Data Center (NNDC):  https://www.nndc.bnl.gov/nudat3/mird/

International Atomic Energy Agency (IAEA) Livechart:  https://www-nds.iaea.org/relnsd/vcharthtml/VChartHTML.html

Reference Links

ICRP Report 107: https://www.icrp.org/publication.asp?id=ICRP%20Publication%20107

Graves et al. Dose Point Kernels: https://doi.org/10.1002/mp.13789

MIRD Decay Schemes 2nd Edition: https://sites.snmmi.org/SNMMI-MAIN/iCore/Store/StoreLayouts/Item_Detail.aspx?iProductCode=0-932004-80-6

 

 

 

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